What is the best way to handle configuration migration?

[philpax]

Sometimes, you just gotta change how your config's being stored / what's being stored, but you want to make sure that you aren't going to lose user data while doing so. What's the cleanest way of doing this, preferably while remaining a nice and clean separation between versions?

This seems like it might be a bit complicated because the Configuration is automatically de/serialised - how do you gracefully choose to deserialise with a ConfigurationV1, convert to a ConfigurationV2, and serialise with the ConfigurationV2?

[karashiiro]

I actually have migration classes which run on load and handle this. It's a bit messy, but it works as long as you think it through thoroughly, accounting for all the previous versions a user could be jumping from (which is not ideal).

[karashiiro]

See here.

[karashiiro]

Also note all of the obsolete fields required for proper loading.

[philpax]

Yeah, that's all I can think of as well with the current system (outside of like... having explicit v1: ConfigurationV1 fields). Bit of a shame.